Both parties suffered Senate recruitment setbacks last week when incumbent House members announced their decisions not to run statewide in 2014. But is it too early to declare a recruitment failure for either party in these races?

Despite the reluctance of Republican Rep. Steve King of Iowa and Democratic Rep. John Barrow of Georgia to make bids for the Senate, it's probably too soon to judge either party's fortunes this election cycle. Kyle Trygstad's review of Senate candidate announcement dates in the last cycle shows there's a lot that can happen before the point of no return arrives. (See this Roll Call story: Senate Race Recruitment: Too Early to Fail?)

For example, on this exact date last cycle, then-Rep. Joe Donnelly, D-Ind., entered the Senate race as an underdog. The following candidates hadn't jumped into the race yet: Elizabeth Warren, D-Mass., Heidi Heitkamp, D-N.D., and Deb Fischer, R-Neb. All four are now senators.

Also notable: All four candidates who flipped party control of a seat either announced on this date (Donnelly) or later in the 2012 cycle (Warren, Fischer and Sen. Angus King, I-Maine).

Here's a timeline of when the top eventual Senate nominees jumped into the race last cycle: